This invention relates to semiconductor vapor phase growing apparatus in which substrates made of silicon, germanium or the like are mounted on a support which is rotatable or movable in one or more directions and semiconductor layers are formed epitaxially on the substrates, and more particularly to such apparatus including means for automatically loading and unloading substrates onto and from the support.
The work of arranging, in a predetermined pattern, a plurality of substrates on a support and removing the substrates from the support has been made manually. However, since conventional semiconductor vapor phase growing apparatus is operated at high temperatures and utilizes dangerous or poisonous reaction gases, it has been desired to provide an improved automatic device capable of loading and unloading the substrates without the danger of contacting the gases thereby improving the efficiency. For this reason, in a patent specification filed in Japan later than the instant application, there is disclosed automatic apparatus in which marks or irregularities for detecting the positions of the substrates are disposed about the support for positioning or indexing the support at each predetermined angle in accordance with the marks or irregularities so as to automatically load and unload the substrates. However, the size of the substrates arranged on the support is not always constant. For example, there are wafers having diameters of 4, 5 and 6 inches. Further, the vapor phase growth of respective substrates differs substantially due to the characteristic of the growing apparatus. Accordingly, it is not always necessary to arrange the substrates on the support at a definite spacing in a fixed pattern and, often, it is necessary to modify the arrangement according to the characteristic of the growing apparatus.